linux/drivers/bus/fsl-mc/dprc-driver.c

810 lines
20 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Freescale data path resource container (DPRC) driver
*
* Copyright (C) 2014-2016 Freescale Semiconductor, Inc.
* Author: German Rivera <German.Rivera@freescale.com>
*
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/msi.h>
#include <linux/fsl/mc.h>
#include "fsl-mc-private.h"
#define FSL_MC_DPRC_DRIVER_NAME "fsl_mc_dprc"
struct fsl_mc_child_objs {
int child_count;
struct fsl_mc_obj_desc *child_array;
};
static bool fsl_mc_device_match(struct fsl_mc_device *mc_dev,
struct fsl_mc_obj_desc *obj_desc)
{
return mc_dev->obj_desc.id == obj_desc->id &&
strcmp(mc_dev->obj_desc.type, obj_desc->type) == 0;
}
static int __fsl_mc_device_remove_if_not_in_mc(struct device *dev, void *data)
{
int i;
struct fsl_mc_child_objs *objs;
struct fsl_mc_device *mc_dev;
mc_dev = to_fsl_mc_device(dev);
objs = data;
for (i = 0; i < objs->child_count; i++) {
struct fsl_mc_obj_desc *obj_desc = &objs->child_array[i];
if (strlen(obj_desc->type) != 0 &&
fsl_mc_device_match(mc_dev, obj_desc))
break;
}
if (i == objs->child_count)
fsl_mc_device_remove(mc_dev);
return 0;
}
static int __fsl_mc_device_remove(struct device *dev, void *data)
{
fsl_mc_device_remove(to_fsl_mc_device(dev));
return 0;
}
/**
* dprc_remove_devices - Removes devices for objects removed from a DPRC
*
* @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
* @obj_desc_array: array of object descriptors for child objects currently
* present in the DPRC in the MC.
* @num_child_objects_in_mc: number of entries in obj_desc_array
*
* Synchronizes the state of the Linux bus driver with the actual state of
* the MC by removing devices that represent MC objects that have
* been dynamically removed in the physical DPRC.
*/
static void dprc_remove_devices(struct fsl_mc_device *mc_bus_dev,
struct fsl_mc_obj_desc *obj_desc_array,
int num_child_objects_in_mc)
{
if (num_child_objects_in_mc != 0) {
/*
* Remove child objects that are in the DPRC in Linux,
* but not in the MC:
*/
struct fsl_mc_child_objs objs;
objs.child_count = num_child_objects_in_mc;
objs.child_array = obj_desc_array;
device_for_each_child(&mc_bus_dev->dev, &objs,
__fsl_mc_device_remove_if_not_in_mc);
} else {
/*
* There are no child objects for this DPRC in the MC.
* So, remove all the child devices from Linux:
*/
device_for_each_child(&mc_bus_dev->dev, NULL,
__fsl_mc_device_remove);
}
}
static int __fsl_mc_device_match(struct device *dev, void *data)
{
struct fsl_mc_obj_desc *obj_desc = data;
struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
return fsl_mc_device_match(mc_dev, obj_desc);
}
static struct fsl_mc_device *fsl_mc_device_lookup(struct fsl_mc_obj_desc
*obj_desc,
struct fsl_mc_device
*mc_bus_dev)
{
struct device *dev;
dev = device_find_child(&mc_bus_dev->dev, obj_desc,
__fsl_mc_device_match);
return dev ? to_fsl_mc_device(dev) : NULL;
}
/**
* check_plugged_state_change - Check change in an MC object's plugged state
*
* @mc_dev: pointer to the fsl-mc device for a given MC object
* @obj_desc: pointer to the MC object's descriptor in the MC
*
* If the plugged state has changed from unplugged to plugged, the fsl-mc
* device is bound to the corresponding device driver.
* If the plugged state has changed from plugged to unplugged, the fsl-mc
* device is unbound from the corresponding device driver.
*/
static void check_plugged_state_change(struct fsl_mc_device *mc_dev,
struct fsl_mc_obj_desc *obj_desc)
{
int error;
u32 plugged_flag_at_mc =
obj_desc->state & FSL_MC_OBJ_STATE_PLUGGED;
if (plugged_flag_at_mc !=
(mc_dev->obj_desc.state & FSL_MC_OBJ_STATE_PLUGGED)) {
if (plugged_flag_at_mc) {
mc_dev->obj_desc.state |= FSL_MC_OBJ_STATE_PLUGGED;
error = device_attach(&mc_dev->dev);
if (error < 0) {
dev_err(&mc_dev->dev,
"device_attach() failed: %d\n",
error);
}
} else {
mc_dev->obj_desc.state &= ~FSL_MC_OBJ_STATE_PLUGGED;
device_release_driver(&mc_dev->dev);
}
}
}
/**
* dprc_add_new_devices - Adds devices to the logical bus for a DPRC
*
* @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
* @obj_desc_array: array of device descriptors for child devices currently
* present in the physical DPRC.
* @num_child_objects_in_mc: number of entries in obj_desc_array
*
* Synchronizes the state of the Linux bus driver with the actual
* state of the MC by adding objects that have been newly discovered
* in the physical DPRC.
*/
static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
struct fsl_mc_obj_desc *obj_desc_array,
int num_child_objects_in_mc)
{
int error;
int i;
for (i = 0; i < num_child_objects_in_mc; i++) {
struct fsl_mc_device *child_dev;
struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];
if (strlen(obj_desc->type) == 0)
continue;
/*
* Check if device is already known to Linux:
*/
child_dev = fsl_mc_device_lookup(obj_desc, mc_bus_dev);
if (child_dev) {
check_plugged_state_change(child_dev, obj_desc);
put_device(&child_dev->dev);
continue;
}
error = fsl_mc_device_add(obj_desc, NULL, &mc_bus_dev->dev,
&child_dev);
if (error < 0)
continue;
}
}
/**
* dprc_scan_objects - Discover objects in a DPRC
*
* @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
* @total_irq_count: If argument is provided the function populates the
* total number of IRQs created by objects in the DPRC.
*
* Detects objects added and removed from a DPRC and synchronizes the
* state of the Linux bus driver, MC by adding and removing
* devices accordingly.
* Two types of devices can be found in a DPRC: allocatable objects (e.g.,
* dpbp, dpmcp) and non-allocatable devices (e.g., dprc, dpni).
* All allocatable devices needed to be probed before all non-allocatable
* devices, to ensure that device drivers for non-allocatable
* devices can allocate any type of allocatable devices.
* That is, we need to ensure that the corresponding resource pools are
* populated before they can get allocation requests from probe callbacks
* of the device drivers for the non-allocatable devices.
*/
static int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
unsigned int *total_irq_count)
{
int num_child_objects;
int dprc_get_obj_failures;
int error;
unsigned int irq_count = mc_bus_dev->obj_desc.irq_count;
struct fsl_mc_obj_desc *child_obj_desc_array = NULL;
struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
error = dprc_get_obj_count(mc_bus_dev->mc_io,
0,
mc_bus_dev->mc_handle,
&num_child_objects);
if (error < 0) {
dev_err(&mc_bus_dev->dev, "dprc_get_obj_count() failed: %d\n",
error);
return error;
}
if (num_child_objects != 0) {
int i;
child_obj_desc_array =
devm_kmalloc_array(&mc_bus_dev->dev, num_child_objects,
sizeof(*child_obj_desc_array),
GFP_KERNEL);
if (!child_obj_desc_array)
return -ENOMEM;
/*
* Discover objects currently present in the physical DPRC:
*/
dprc_get_obj_failures = 0;
for (i = 0; i < num_child_objects; i++) {
struct fsl_mc_obj_desc *obj_desc =
&child_obj_desc_array[i];
error = dprc_get_obj(mc_bus_dev->mc_io,
0,
mc_bus_dev->mc_handle,
i, obj_desc);
if (error < 0) {
dev_err(&mc_bus_dev->dev,
"dprc_get_obj(i=%d) failed: %d\n",
i, error);
/*
* Mark the obj entry as "invalid", by using the
* empty string as obj type:
*/
obj_desc->type[0] = '\0';
obj_desc->id = error;
dprc_get_obj_failures++;
continue;
}
/*
* add a quirk for all versions of dpsec < 4.0...none
* are coherent regardless of what the MC reports.
*/
if ((strcmp(obj_desc->type, "dpseci") == 0) &&
(obj_desc->ver_major < 4))
obj_desc->flags |=
FSL_MC_OBJ_FLAG_NO_MEM_SHAREABILITY;
irq_count += obj_desc->irq_count;
dev_dbg(&mc_bus_dev->dev,
"Discovered object: type %s, id %d\n",
obj_desc->type, obj_desc->id);
}
if (dprc_get_obj_failures != 0) {
dev_err(&mc_bus_dev->dev,
"%d out of %d devices could not be retrieved\n",
dprc_get_obj_failures, num_child_objects);
}
}
/*
* Allocate IRQ's before binding the scanned devices with their
* respective drivers.
*/
if (dev_get_msi_domain(&mc_bus_dev->dev) && !mc_bus->irq_resources) {
if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
dev_warn(&mc_bus_dev->dev,
"IRQs needed (%u) exceed IRQs preallocated (%u)\n",
irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
}
error = fsl_mc_populate_irq_pool(mc_bus,
FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
if (error < 0)
return error;
}
if (total_irq_count)
*total_irq_count = irq_count;
dprc_remove_devices(mc_bus_dev, child_obj_desc_array,
num_child_objects);
dprc_add_new_devices(mc_bus_dev, child_obj_desc_array,
num_child_objects);
if (child_obj_desc_array)
devm_kfree(&mc_bus_dev->dev, child_obj_desc_array);
return 0;
}
/**
* dprc_scan_container - Scans a physical DPRC and synchronizes Linux bus state
*
* @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
*
* Scans the physical DPRC and synchronizes the state of the Linux
* bus driver with the actual state of the MC by adding and removing
* devices as appropriate.
*/
static int dprc_scan_container(struct fsl_mc_device *mc_bus_dev)
{
int error;
struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
fsl_mc_init_all_resource_pools(mc_bus_dev);
/*
* Discover objects in the DPRC:
*/
mutex_lock(&mc_bus->scan_mutex);
error = dprc_scan_objects(mc_bus_dev, NULL);
mutex_unlock(&mc_bus->scan_mutex);
if (error < 0) {
fsl_mc_cleanup_all_resource_pools(mc_bus_dev);
return error;
}
return 0;
}
/**
* dprc_irq0_handler - Regular ISR for DPRC interrupt 0
*
* @irq: IRQ number of the interrupt being handled
* @arg: Pointer to device structure
*/
static irqreturn_t dprc_irq0_handler(int irq_num, void *arg)
{
return IRQ_WAKE_THREAD;
}
/**
* dprc_irq0_handler_thread - Handler thread function for DPRC interrupt 0
*
* @irq: IRQ number of the interrupt being handled
* @arg: Pointer to device structure
*/
static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
{
int error;
u32 status;
struct device *dev = arg;
struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
struct fsl_mc_io *mc_io = mc_dev->mc_io;
struct msi_desc *msi_desc = mc_dev->irqs[0]->msi_desc;
dev_dbg(dev, "DPRC IRQ %d triggered on CPU %u\n",
irq_num, smp_processor_id());
if (!(mc_dev->flags & FSL_MC_IS_DPRC))
return IRQ_HANDLED;
mutex_lock(&mc_bus->scan_mutex);
if (!msi_desc || msi_desc->irq != (u32)irq_num)
goto out;
status = 0;
error = dprc_get_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
&status);
if (error < 0) {
dev_err(dev,
"dprc_get_irq_status() failed: %d\n", error);
goto out;
}
error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
status);
if (error < 0) {
dev_err(dev,
"dprc_clear_irq_status() failed: %d\n", error);
goto out;
}
if (status & (DPRC_IRQ_EVENT_OBJ_ADDED |
DPRC_IRQ_EVENT_OBJ_REMOVED |
DPRC_IRQ_EVENT_CONTAINER_DESTROYED |
DPRC_IRQ_EVENT_OBJ_DESTROYED |
DPRC_IRQ_EVENT_OBJ_CREATED)) {
unsigned int irq_count;
error = dprc_scan_objects(mc_dev, &irq_count);
if (error < 0) {
/*
* If the error is -ENXIO, we ignore it, as it indicates
* that the object scan was aborted, as we detected that
* an object was removed from the DPRC in the MC, while
* we were scanning the DPRC.
*/
if (error != -ENXIO) {
dev_err(dev, "dprc_scan_objects() failed: %d\n",
error);
}
goto out;
}
if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
dev_warn(dev,
"IRQs needed (%u) exceed IRQs preallocated (%u)\n",
irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
}
}
out:
mutex_unlock(&mc_bus->scan_mutex);
return IRQ_HANDLED;
}
/*
* Disable and clear interrupt for a given DPRC object
*/
static int disable_dprc_irq(struct fsl_mc_device *mc_dev)
{
int error;
struct fsl_mc_io *mc_io = mc_dev->mc_io;
/*
* Disable generation of interrupt, while we configure it:
*/
error = dprc_set_irq_enable(mc_io, 0, mc_dev->mc_handle, 0, 0);
if (error < 0) {
dev_err(&mc_dev->dev,
"Disabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
error);
return error;
}
/*
* Disable all interrupt causes for the interrupt:
*/
error = dprc_set_irq_mask(mc_io, 0, mc_dev->mc_handle, 0, 0x0);
if (error < 0) {
dev_err(&mc_dev->dev,
"Disabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
error);
return error;
}
/*
* Clear any leftover interrupts:
*/
error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0, ~0x0U);
if (error < 0) {
dev_err(&mc_dev->dev,
"Disabling DPRC IRQ failed: dprc_clear_irq_status() failed: %d\n",
error);
return error;
}
return 0;
}
static int register_dprc_irq_handler(struct fsl_mc_device *mc_dev)
{
int error;
struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
/*
* NOTE: devm_request_threaded_irq() invokes the device-specific
* function that programs the MSI physically in the device
*/
error = devm_request_threaded_irq(&mc_dev->dev,
irq->msi_desc->irq,
dprc_irq0_handler,
dprc_irq0_handler_thread,
IRQF_NO_SUSPEND | IRQF_ONESHOT,
dev_name(&mc_dev->dev),
&mc_dev->dev);
if (error < 0) {
dev_err(&mc_dev->dev,
"devm_request_threaded_irq() failed: %d\n",
error);
return error;
}
return 0;
}
static int enable_dprc_irq(struct fsl_mc_device *mc_dev)
{
int error;
/*
* Enable all interrupt causes for the interrupt:
*/
error = dprc_set_irq_mask(mc_dev->mc_io, 0, mc_dev->mc_handle, 0,
~0x0u);
if (error < 0) {
dev_err(&mc_dev->dev,
"Enabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
error);
return error;
}
/*
* Enable generation of the interrupt:
*/
error = dprc_set_irq_enable(mc_dev->mc_io, 0, mc_dev->mc_handle, 0, 1);
if (error < 0) {
dev_err(&mc_dev->dev,
"Enabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
error);
return error;
}
return 0;
}
/*
* Setup interrupt for a given DPRC device
*/
static int dprc_setup_irq(struct fsl_mc_device *mc_dev)
{
int error;
error = fsl_mc_allocate_irqs(mc_dev);
if (error < 0)
return error;
error = disable_dprc_irq(mc_dev);
if (error < 0)
goto error_free_irqs;
error = register_dprc_irq_handler(mc_dev);
if (error < 0)
goto error_free_irqs;
error = enable_dprc_irq(mc_dev);
if (error < 0)
goto error_free_irqs;
return 0;
error_free_irqs:
fsl_mc_free_irqs(mc_dev);
return error;
}
/**
* dprc_probe - callback invoked when a DPRC is being bound to this driver
*
* @mc_dev: Pointer to fsl-mc device representing a DPRC
*
* It opens the physical DPRC in the MC.
* It scans the DPRC to discover the MC objects contained in it.
* It creates the interrupt pool for the MC bus associated with the DPRC.
* It configures the interrupts for the DPRC device itself.
*/
static int dprc_probe(struct fsl_mc_device *mc_dev)
{
int error;
size_t region_size;
struct device *parent_dev = mc_dev->dev.parent;
struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
bool mc_io_created = false;
bool msi_domain_set = false;
u16 major_ver, minor_ver;
if (!is_fsl_mc_bus_dprc(mc_dev))
return -EINVAL;
if (dev_get_msi_domain(&mc_dev->dev))
return -EINVAL;
if (!mc_dev->mc_io) {
/*
* This is a child DPRC:
*/
if (!dev_is_fsl_mc(parent_dev))
return -EINVAL;
if (mc_dev->obj_desc.region_count == 0)
return -EINVAL;
region_size = resource_size(mc_dev->regions);
error = fsl_create_mc_io(&mc_dev->dev,
mc_dev->regions[0].start,
region_size,
NULL,
FSL_MC_IO_ATOMIC_CONTEXT_PORTAL,
&mc_dev->mc_io);
if (error < 0)
return error;
mc_io_created = true;
/*
* Inherit parent MSI domain:
*/
dev_set_msi_domain(&mc_dev->dev,
dev_get_msi_domain(parent_dev));
msi_domain_set = true;
} else {
/*
* This is a root DPRC
*/
struct irq_domain *mc_msi_domain;
if (dev_is_fsl_mc(parent_dev))
return -EINVAL;
error = fsl_mc_find_msi_domain(parent_dev,
&mc_msi_domain);
if (error < 0) {
dev_warn(&mc_dev->dev,
"WARNING: MC bus without interrupt support\n");
} else {
dev_set_msi_domain(&mc_dev->dev, mc_msi_domain);
msi_domain_set = true;
}
}
error = dprc_open(mc_dev->mc_io, 0, mc_dev->obj_desc.id,
&mc_dev->mc_handle);
if (error < 0) {
dev_err(&mc_dev->dev, "dprc_open() failed: %d\n", error);
goto error_cleanup_msi_domain;
}
error = dprc_get_attributes(mc_dev->mc_io, 0, mc_dev->mc_handle,
&mc_bus->dprc_attr);
if (error < 0) {
dev_err(&mc_dev->dev, "dprc_get_attributes() failed: %d\n",
error);
goto error_cleanup_open;
}
error = dprc_get_api_version(mc_dev->mc_io, 0,
&major_ver,
&minor_ver);
if (error < 0) {
dev_err(&mc_dev->dev, "dprc_get_api_version() failed: %d\n",
error);
goto error_cleanup_open;
}
if (major_ver < DPRC_MIN_VER_MAJOR ||
(major_ver == DPRC_MIN_VER_MAJOR &&
minor_ver < DPRC_MIN_VER_MINOR)) {
dev_err(&mc_dev->dev,
"ERROR: DPRC version %d.%d not supported\n",
major_ver, minor_ver);
error = -ENOTSUPP;
goto error_cleanup_open;
}
mutex_init(&mc_bus->scan_mutex);
/*
* Discover MC objects in DPRC object:
*/
error = dprc_scan_container(mc_dev);
if (error < 0)
goto error_cleanup_open;
/*
* Configure interrupt for the DPRC object associated with this MC bus:
*/
error = dprc_setup_irq(mc_dev);
if (error < 0)
goto error_cleanup_open;
dev_info(&mc_dev->dev, "DPRC device bound to driver");
return 0;
error_cleanup_open:
(void)dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
error_cleanup_msi_domain:
if (msi_domain_set)
dev_set_msi_domain(&mc_dev->dev, NULL);
if (mc_io_created) {
fsl_destroy_mc_io(mc_dev->mc_io);
mc_dev->mc_io = NULL;
}
return error;
}
/*
* Tear down interrupt for a given DPRC object
*/
static void dprc_teardown_irq(struct fsl_mc_device *mc_dev)
{
struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
(void)disable_dprc_irq(mc_dev);
devm_free_irq(&mc_dev->dev, irq->msi_desc->irq, &mc_dev->dev);
fsl_mc_free_irqs(mc_dev);
}
/**
* dprc_remove - callback invoked when a DPRC is being unbound from this driver
*
* @mc_dev: Pointer to fsl-mc device representing the DPRC
*
* It removes the DPRC's child objects from Linux (not from the MC) and
* closes the DPRC device in the MC.
* It tears down the interrupts that were configured for the DPRC device.
* It destroys the interrupt pool associated with this MC bus.
*/
static int dprc_remove(struct fsl_mc_device *mc_dev)
{
int error;
struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
if (!is_fsl_mc_bus_dprc(mc_dev))
return -EINVAL;
if (!mc_dev->mc_io)
return -EINVAL;
if (!mc_bus->irq_resources)
return -EINVAL;
if (dev_get_msi_domain(&mc_dev->dev))
dprc_teardown_irq(mc_dev);
device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
if (dev_get_msi_domain(&mc_dev->dev)) {
fsl_mc_cleanup_irq_pool(mc_bus);
dev_set_msi_domain(&mc_dev->dev, NULL);
}
fsl_mc_cleanup_all_resource_pools(mc_dev);
error = dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
if (error < 0)
dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);
if (!fsl_mc_is_root_dprc(&mc_dev->dev)) {
fsl_destroy_mc_io(mc_dev->mc_io);
mc_dev->mc_io = NULL;
}
dev_info(&mc_dev->dev, "DPRC device unbound from driver");
return 0;
}
static const struct fsl_mc_device_id match_id_table[] = {
{
.vendor = FSL_MC_VENDOR_FREESCALE,
.obj_type = "dprc"},
{.vendor = 0x0},
};
static struct fsl_mc_driver dprc_driver = {
.driver = {
.name = FSL_MC_DPRC_DRIVER_NAME,
.owner = THIS_MODULE,
.pm = NULL,
},
.match_id_table = match_id_table,
.probe = dprc_probe,
.remove = dprc_remove,
};
int __init dprc_driver_init(void)
{
return fsl_mc_driver_register(&dprc_driver);
}
void dprc_driver_exit(void)
{
fsl_mc_driver_unregister(&dprc_driver);
}